Reversing steam-turbine.



N0. 854,482. PATENTED MAY 21, 1907.

W. G. GARDINER.

REVERSING STEAM TURBINE.

APPLICATION FILED JULY 31, 1906.

' s SHEETS-SHEET 1.

A/VE/VTOP m: NORRIS PBTERS co., WASHINm'DN n. c

TATENTED MAY 21, 1907.

W. G. GARDINBR. REVERSING STEAM TURBINE.

A?PLIOATION FILED JULYBI, 1906.

3 SHEETS-SHEET 2.

ATTOF/VEYLS No. 854,482. PATENTED MAY 21, 1907.

' W. G. GARDINER.

RBVERSING STEAM TURBINE.

APPLICATION FILED JULY31, 190a.

- a SHEETS-SHEET a.

w/rzvlfssfs: 4 A Wzzgyvgr oe W V I I z (2772 bearings A A UNITED STATESPATENT OFFICE.

REVERSING STEAM-TURBINE.

Specification of Letters Patent.

Patented May 21, 1907.

Application filed July 31,1906. Serial No. 328.498.

T0 ntZZ whom it hula concern:

Be it known" that I, WILLIAM CHARLES GAEDINER, asubject of the King ofGreat Britain, residing at 17 St. Clement street, Aberdeen, Scotland,marine engineer, have invented an Improved Multiple-Expansion ReversingSteam Turbine or Rotary Engine, of which the following is aspecification.

This invention relates to multiple expansion reversible steam turbineswherein rotary distribution valves are employed for the purpose ofvarying the expansion of the steam and determining the direction ofrevolution of the rotor.

In the accompanying drawings Figure 1 is a central vertical.longitudinal section (through the steam inlet ports) of a horizontaltriple-expansion reversible steam turbine embodying the improvementswhich form the subject of the present invention, Figs. 2;, 3, 4, and 5being transverse sections on lines 22, 3-3, 4-4 and 55 respectively ofFig. 1. In Fig. 6 are shown, by way of example, a series of modifiedforms of bucket.

Similar letters of reference denote corresponding parts throughout thedrawings.

A is the rotor shaft, which is arranged axi ally of the cylindrical bodyportion of the turbine casing B and passes out through stuffing boxes bb in the end covers thereof, the shaft being journaled, externally ofthe casing, in The rotor comprises (for a tripleexpansion turbine asillustrated) a se ries of three bucket wheels C C C mounted fast, sideby side, upon the shaft A so as to revolve in corresponding chambers B BB in the casing, the second and third bucket wheels 0 C being ofprogressively increased diameter and their chambers B B correspondinglyenlarged. to accommodate them.

According to the present invention each bucket wheel C C C is made of abreadth considerably greater in the direction of the rotor axis than hasheretofore been usual in turbines of this class, the increased breadthbeing divided, in the case of each wheel, into a series of sections 0, cc (three being shown in the example illustrated) by means of partitionsdd which, like the outer ends (Z d of the bucket wheels, are disposed inplanes perpendicular to the rotor axis. The several sections 0 c c ofeach wheel are pref erably (as shown) of the same breadth and diameter,while the successive wheels C C C are of progressively increaseddiameter, or breadth, or both, in order to afford space for theexpansion of the steam as it passes from one bucket wheel chamber to thenext. For the same reason the buckets of successive wheels may be ofprogressively increased depth.

The buckets in each circumferential series constituting a bucket wheelsection 0 c or c are separated as before by flat-faced radlal vanes Ewhich intersect the wheel ends cl (1 and the section partitions d d atright angles, the buckets, which are of equal length circumferentiallyof the rotor in all the sections of one wheel, being preferably arrangedso that those of each successive section have an angular advance onthose of the preceding section.

The steam ports in the casing are, for each bucket wheel chamber,disposed symmetrically on either side of a longitudinal axial plane9c-0c which may be termed the median plane of the turbine and which inthe example illustrated is vertical, the two inlet ports F F usedrespectively for opposite directions of running being equidistant atopposite sides of said plane while the two ex haust ports G G open fromthe bucket wheel chamber by way of tangential passages situated likewiseat opposite sides of the plane :t-ac but at a greater distance therefromthan the inlet ports F F. The steam ports F and Gare divided intosections (whereof those of the inlet ports F are indicated at f f f inFig. 1) separated by partitions so as to register, lengthwise of therotor axis, with the corresponding sections 0 c c of the respectivebucket wheels, the major dimension of each port section (moreparticularly in the case of the inlet ports F) being preferably disposedlengthwise of the rotor axis.

The circiunscribing wall of each bucket wheel chamber B B 13, instead ofembracing the wheel closely around its entire periphery fits the wheelclosely only around that portion of its periphery which extends, by wayof the inlet ports F F,"lrom the one exhaust port G to the other, theremainder of the chamber .Wall (in the example illustrated, the lowerpart) being made of greater radius than the bucket wheel. Consequentlythere is provided between the exhaust ports G G a continuous channel Hthrough which the steam, after having struck and acted upon a vane E asthe latter passed the open inlet port F, finds a partially free passagewhereby to travel around the periphery of the wheel to the open exhaustport G at the opposite side of the median plane, the steam in its coursealong the channel H being enabled to act successively upon all the vanesE which for the time being intervene between the inlet and exhaust portswhich are open.

The enlarged portion of each bucketwheel chamber B B B which constitutesthe channel H may be of constant radius as shown by way of example inFig. 2. Or, in order to increase the propulsive effect of the steam byenabling it to impinge upon successive vanes E at the most favorableangle, the radial enlargement or channel H may take the form of acircumferentially extending series of cavities having either plane orcurved surfaces (as indicated for example in Figs. 3 and 4 respectively)of such configuration as may be found best adapted for the purpose. Insuch cases the wall of the chamber may, as indicated at h, approachsomewhat closely the periphery of the bucket wheel between successivecavities.

In order to further assist the propulsive effect of the steam, eachbucket may be contracted in width, or made of zig-zag form, at a pointor points in its circumferential length, so as to offer additionalsurfaces against which the steam can impinge, or exert pressure due toits expansion, while traveling around the channel H, the contractions inthe width of the buckets causing the latter to serve to a certain extentas what may be termed expansion nozzles. Several forms of suchcontracted and zig-zag buckets are in dicated by way of example in Fig.6, the bucket shown at 6 therein being plain, while those shown at 6 and6 have their sides formed by fiat and curved convergent surfacesrespectively. The. buckets shown at 6 6 6 and 6'' are of various typesof zigzag configuration.

A series of sector-shaped rotary steam distribution valves J J J aremounted fast side by side upon a spindle K which extends, in the medianplane 9cx and preferably parallel to the rotor shaft A, through a seriesof valve chests L If L correspondin respectively to the bucket wheelchambers 1 B B The inlet ports F of each bucket wheel chamber open. intothe corresponding valve chest, in positions symmetrically disposed onopposite sides of the median plane, at a semicircular or segmental faceover which the sector-shaped valve is fitted to be moved by the partialrotation of the spindle K, while the exhaust ports G of each. bucketwheel chamber open similarly but into the next succeeding valve chest.The valve J has inlet ports 7" adapted to register alternatively Withthose F of the high pressure valve chest L and each succeeding valve Jand J is provided with both steam inlet ports f and exhaust .ports 9adapted to register with those F and G in the respective valve chests insuch manner that When the spindle K is turned through certain angle ineither direction, the steam inlet ports on one side and the exhaustports on the opposite side of the median plane ac m, which appertain tothe sev eral bucket wheel chambers, will be opened simultaneously andthose on the opposite side of said plane will be closed, and vice versa.The arrangement is such that steam admitted to the high pressure valvechest L from the main steam pipe M will pass thence round the firstbucket wheel C and, leaving the corresponding chamber by the exhaustport G thereof, will enter the intermediate valve chest L and so on,circulating round the rotor always in the same direction with the resultthat the rotor will be caused to revolve in the direction correspondingto that in which the spindle K was turned.

Each valve J J 2 J is divided into sections j j 7' corresponding tothose of the steam and exhaust ports F and G over which it works.

The valve chests L I, L are separated from one another by partitions Zand are preferably closed externally by a single cover L, the valvespindle K working in bearings halved together about the transverse planepassing through the spindle axis at right angles to the median plane00-90.

The exhaust ports G of the low pressure bucket wheel chamber B deliverinto passages Gr' (Fig. 5) which may extend the greater part of the wayround the correspond ing sides of the final exhaust valve chest Lwherein the valve J is fitted to turn in contact with a face which (likethat of the valve) may be completely cylindrical so as the moreconveniently to afford the requisite area of port opening, the exhaustpipe N opening out at the farther end ofthe valve chest as indi cated inFig. 1.

It will be obvious that the speed of revoluv tion of the rotor may beregulated, independently of the throttle valve, by turning the spindle Kso as to cause the various ports to be opened to a greater or lessextent. If a condenser be coupled to the exhaust pipe N, its action willmaterially assist the propulsive effect of the steam in whicheverdirection the latter is discharged through the final exhaust valve J.

The radial dimensions of successive valve chests and valves may, asindicated, be increased progressively so as to afford the requisitecapacity within each chest for the steam passed through it, and thusobviate the necessity of employing intermediate receivers for the steam.I

As the inlet and exhaust passages appertaining to each bucket wheelchamber are independent and distinct from one another, the exhaustpassages G may be provided with non-return valves (not shown).

In consequence of the relative arrangement of the inlet ports F andexhaust ports G in each bucket wheel chamber, it follows that thepassages connecting the exhaust port openings in the bucket wheelchamber and the next valve chest respectively are of considerable lengthand are always open, from their commencement in the bucket wheel chamberto the valve face whereat they are controlled. Hence, when the rotor isrevolving in either direction, that exhaust passage which for the timebeing is out of use constitutes in effect what may be termed an eddychamber or steam abutment pocket in rear of the vanes E as these passforward on leaving the inlet port opening. This eddy chamber )ecomesfilled with steam at about the pressure of the steam then entering thebucket wheel chamber through the adjacent inlet port, the steam in theeddy chamber serving as a kind of reaction-cushion or elastic abutmentbehind the successive vanes, with the result that the engine operatesnot only by impact but also byreaction and that the propulsive force ofthe steam is correspondingly increased or economized.

F or the purpose of enabling wear to be taken up between the faces ofthe valves J J J J and their seats in the respective valve chests I If LL, each valve may be fitted with an independently adjustable shoe orshoes as indicated at 0. These shoes may be made adjustable eitherautomatically by the pressure of the steam from within the respectivevalve chests, or by suitable mechanism (not shown) provided for thepurpose. Or each valve while adapted to turn with the spindle K might bemade adjustable as a whole transversely of said spindle, as for examplein substantially the same manner as in the case of a Corliss rotarysteam valve.

The entire se ies of bucket wheels C C C, whether cast in one or builtup in sections, are preferably combined in a single structure supportedby means of spider frames 0 keyed upon the rotor shaft A, while adjacentbucket wheels and the chambers wherein they revolve are separated fromone another by a steam-tight closure formed by a spring ring or rings asat p. These rings would have lap joints and each would preferably bereceived and lit within grooves provided in both surfaces between whichit forms a oint.

Similar spring rin s may be employedas at q to form a steam-tightclosure around the valve spindle K where the latter passes througl'ieach of the partitions Z separating the successive valve chests. Thespindle K Would pass out through the end wall of the high pressure valvechest L by way of a stuffing box as at and be coupled externally thereofto any convenient means for effecting the necessary angular adjustmentof the spindle and valves.

The valve chest cover L being halved about the axial transverse planethrough the spindle K as already mentioned, the fitting of the springrings (7 is rendered easy. The turbine casing B is also preferablydivided on the transverse plane passing through the rotor axis at rightangles to the median plane ax so as to afford ready access to theinterior and permit of the rings 1) being fitted in plac Claims.

1. In a multiple expansion reversible steam turbine, a series ofbucket-wheels of progressively increasin diameter, a casing forming aseries of chambers of progressively increasing size in which said bucketwheels rotate, each chamber being in the shape of segments of twocylinders and of such cross sectional area that the internal diameterthe one segment of each chamber from outlet pipe to outlet pipe isgreater than the diameter of the bucket wheel which the casing incloses,and the internal diameter of the other segment of each chamber fromoutlet pipe to outlet pipe is substantially the same as the diameter ofthe corresponding bucket-wheel so that a channel is left on the one sideonly, between the casing and the bucket-wheels for the passage of thesteam, substantially as and for the purpose specified.

2. In a multiple expansion reversible steam turbine, a series ofbucket-wheels of progressivelyincreasing size, a series of chambers ofprogressively increasing size in which thebucket wheels rotate, eachchamber having its lower side of greater internal diameter than theexternal diameter of the corresponding bucket wheel, the bucket wheelbeing provided with buckets each of which is divided in the axialdirection into a series of sections by means of partitions disposed inplanes perpendicular to the axis of rotation substantially as described.

3. In a multiple expansion reversible steam turbine, a series ofbucket-wheels of progressivelyincreasing size, a series of chambers ofprogressivelyincreasing size in which said bucket wheels rotate, eachchamber having its lower side of greater internal diameter than theexternal diameter of the corresponding bucket-wheel, and bucketscontracted. in their width and made of irregular shape so as to beadapted to offer additional surfaces against which the steam canimpinge, substantially as specified.

4. In a multiple expansion reversible steam turbine, the combinationwith a casing fomed of a series of bucket wheel chambers, valve chests,and exhaust chambers, and a series of bucket wheels each mounted torotate in one of the bucket wheel chambers, of a series of sector-shapedvalves moving together on the same axis, each valve being mounted tooscillate in one of the valve chests, and having pairs of inlet andoutlet ports for controllingthe entrance of the steam into thebucket-wheel chambers substantially as specified.

5. In a multiple expansion reversible steam turbine, a casing formed ofa series of bucket wheel chambers, valve chests, and exhaust chambers, aseries of bucket wheels, each mounted to rotate in one of the bucketwheel chambers, a series of sector-shaped valves all of progressivelyincreasing crosssectional area, and adjustable wearing shoes for saidvalves.

6. In a multiple-expansion steam turbine, a series of bucket wheels ofprogressively increasing size, a series of chambers of pro gressivelyincreasing size in which said bucket wheels rotate, each chamber havingits lower side of greater internal diameter than the external diameterof the bucket wheel, so as to form a narrow channel for the passage ofthe steam between the walls of the chamber and the bucket wheels, thewalls of said portion of the chamber having a series of cavitiesextending parallel to the axis of the corresponding bucket wheel, thewall of the chamber between the cavities extending adjacent to theperiphery of the bucket wheel, substantially as described.

7. A multiple-expansion reversible steam turbine, comprising a casingcontaining a series of bucket wheel chambers, valve chests and exhaustchambers of progressively increasing cross-sectional area, a series ofbucket wheels of progressively increasing cross sectional area, eachwheel being of smaller cross-sectional area in its lower part than thatof the ch amber in Which it rotates, a shaft extending through thebucket wheel chambers and carrying the bucket-wheels, thrust ringsfitting into annular grooves formed on the inner surfaces of thebucketwheel chambers, and valve chests respectively, a sector-shapedhigh pressure valve with a series of pairs of inlet ports, andintermediate sector-shaped valves with a series of pairs of inlet andoutlet ports, each valve being fitted with an adjustable wearing shoeand fitted on a shaft extending the whole length of the valve chests,with means for oscillating the shaft, an intermediate body portion ofthe casing having series of pairs of inlet ports leading from the valvechests to the bucket-chambers, said portion of the casing constitutingsteam-tight Working surfaces for the valves and bucket wheels, acylindrical exhaust valve chest, and an exhaust pipe opening out of thevalve chest, substantially as described.

WILLIAM CHARLES GARDINER.

